Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – John Walker ran a father and son spy ring, passing classified material to the Soviet Union from 1967 to 1985. Walker was a Navy communication specialist with financial difficulties when he walked into the Soviet Embassy and sold a piece of cyphering equipment. Navy and Defense officials said that Walker enabled the Soviet Union to unscramble military communications and pinpoint the location of U.S. submarines at all times. As part of his plea deal, prosecutors promised leniency for Walker's son Michael Walker, a former Navy seaman. Click through the gallery to see other high-profile leak scandals the United States has seen over the years.

Hide Caption

1 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Military analyst Daniel Ellsberg leaked the 7,000-page Pentagon Papers in 1971. The top-secret documents revealed that senior American leaders, including three presidents, knew the Vietnam War was an unwinnable, tragic quagmire. Further, they showed that the government had lied to Congress and the public about the progress of the war. Ellsberg surrendered to authorities and was charged as a spy. During his trial, the court learned that President Richard Nixon's administration had embarked on a campaign to discredit Ellsberg, illegally wiretapping him and breaking into his psychiatrist's office. All charges against him were dropped. Since then he has lived a relatively quiet life as a respected author and lecturer.

Hide Caption

2 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Jonathan Pollard is a divisive figure in U.S.-Israeli relations. The former U.S. Navy intelligence analyst was caught spying for Israel in 1985 and was sentenced in 1987 to life imprisonment. Previously, the United States and Israel discussed his possible release as part of efforts to save fragile Middle East peace negotiations, according to sources familiar with the talks. On July 28, 2015, Pollard's lawyer announced that the convicted spy had been granted parole and would be released on November 21 -- exactly 30 years after his arrest.

Hide Caption

3 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Wen Ho Lee was a scientist at the Los Alamos Laboratory in New Mexico who was charged with 59 counts of downloading classified information onto computer tapes and passing it to China. Lee eventually agreed to plead guilty to a count of mishandling classified information after prosecutors deemed their case to be too weak. He was released after nine months in solitary confinement. Lee later received a $1.6 million in separate settlements with the government and five news agencies after he sued them, accusing the government of leaking damaging information about him to the media.

Hide Caption

4 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Members of the Bush administration were accused retaliating against Valerie Plame, pictured, by blowing her cover in 2003 as a U.S. intelligence operative, after her husband, former Ambassador Joe Wilson, wrote a series of New York Times op-eds questioning the basis of certain facts the administration used to make the argument to go to war in Iraq.

Hide Caption

5 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – In 2007, Lewis "Scooter" Libby, Vice President Dick Cheney's former chief of staff, was convicted on charges related to the leak of the identity of CIA operative Valerie Plame. Libby was convicted of obstruction of justice and perjury in connection with the case. His 30-month sentence was commuted by President George W. Bush. Cheney told a special prosecutor in 2004 that he had no idea who leaked the information.

Hide Caption

6 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Aldrich Ames, a 31-year CIA employee, pleaded guilty to espionage charges in 1994 and was sentenced to life in prison. Ames was a CIA case worker who specialized in Soviet intelligence services and had been passing classified information to the KGB since 1985. U.S. intelligence officials believe that information passed along by Ames led to the arrest and execution of Russian officials they had recruited to spy for them.

Hide Caption

7 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Robert Hanssen pleaded guilty to espionage charges in 2001 in return for the government not seeking the death penalty. Hanssen began spying for the Soviet Union in 1979, three years after going to work for the FBI and prosecutors said he collected $1.4 million for the information he turned over to the Cold War enemy. In 1981, Hanssen's wife caught him with classified documents and convinced him to stop spying, but he started passing secrets to the Soviets again four years later. In 1991, he broke off relations with the KGB, but resumed his espionage career in 1999, this time with the Russian Intelligence Service. He was arrested after making a drop in a Virginia park in 2001.

Hide Caption

8 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Army Pvt. Bradley Manning was convicted July 30 of stealing and disseminating 750,000 pages of classified documents and videos to WikiLeaks, and the counts against him included violations of the Espionage Act. He was found guilty of 20 of the 22 charges but acquitted of the most serious charge -- aiding the enemy. Manning was sentenced to 35 years in military prison in 2013.

Hide Caption

9 of 10

Photos:Sharing secrets: U.S. intelligence leaks

Sharing secrets: U.S. intelligence leaks – Former intelligence contractor Edward Snowden revealed himself as the leaker of details of U.S. government surveillance programs run by the U.S. National Security Agency to track cell phone calls and monitor the e-mail and Internet traffic of virtually all Americans. Snowden has been granted temporary asylum in Russia after initially fleeing to Hong Kong. He has been charged with three felony counts, including violations of the U.S. Espionage Act, over the leaks.

Hide Caption

10 of 10

Story highlights

Kerry is no longer traveling to the Mideast on Wednesday, source tells CNN

Kerry says there's "no agreement" with regards to any prisoner

Pollard is a former U.S. intelligence agent convicted of spying for Israel

Palestinian lawmaker says no deal imminent, alleges Israeli ruse

Jonathan Pollard, the former U.S. intelligence agent who was convicted of spying for Israel, could be released before the Jewish holiday of Passover as part of efforts to save Israeli-Palestinian peace negotiations, an Israeli official involved in the talks told CNN.

Suggestions for deals for Pollard's release have been floated over the years but have not materialized. Passover starts on April 14.

Talk of Pollard's possible release came as Secretary of State John Kerry traveled to Israel on Monday to try to mediate a dispute between Israel and the Palestinians over the release of Palestinian prisoners. Kerry was in Belgium on Tuesday.

He was expected to go back to Israel on Wednesday and to visit Ramallah, West Bank, but a senior State Department official told CNN that trip is no longer happening.

Kerry stated Tuesday night that "no agreement has been reached with respect to any prisoner" -- be it Pollard, whom he was asked about, or anyone else -- though talks involving all parties are ongoing in hopes of reaching a broader agreement.

JUST WATCHED

Who is Jonathan Pollard?

MUST WATCH

JUST WATCHED

U.S., Israel discuss release of spy

MUST WATCH

U.S., Israel discuss release of spy01:43

"At this point in time, no agreement has been reached with respect to any prisoner, not even the ones that at this moment are at issue in terms of the transfer. The Cabinet in Israel has to vote. I'm not sure exactly when that might take place or not. So there is no agreement at this point in time regarding anyone, or any specific steps, there are a lot of different possibilities in play," Kerry said.

"It is difficult, it is emotional, it requires huge decisions, some of them with great political difficulty," he continued. "... We are continuing, even now ... to find the best way forward."

White House spokesman Jay Carney said Tuesday that President Barack Obama hasn't decided whether to release the convicted spy at Israel's request.

"The Israelis frequently raise this issue, and they have raised this issue in our discussions," Carney said. "Beyond that, I'm not going to get ahead of the work that Secretary Kerry is doing and the conversations that he's having."

Pollard's possible release was being discussed as part of a broader agreement that has not been finalized, according to sources familiar with the talks.

In exchange for the release, the sources have said that Israel would have to make significant concessions to the Palestinians, which could include a settlement freeze, the release of additional prisoners beyond the current group in dispute and an agreement to continue peace negotiations beyond the end-of-April deadline.

Pollard was convicted in 1987 of spying for Israel and is serving a life sentence in the United States. His imprisonment has been a source of tension between the United States and Israel.

The Israeli official said the parameters of a deal still emerging include negotiations with the Palestinians continuing into 2015, and an agreement that during that time, Palestinians would refrain from taking their case to international bodies.

However, Mustafa Barghouti, a Palestinian lawmaker who met Monday with Palestinian Authority President Mahmoud Abbas to discuss Kerry's efforts, said the Palestinian leadership believes the Israelis are making claims of an "emerging deal" to create an impression that a breakthrough is imminent so that when it falls apart, it can be blamed on the Palestinians.

Barghouti doubted the notion that the Palestinians were on the verge of signing a deal and said Abbas is increasingly convinced that Israel is not interested in any process that would lead to Palestinian statehood.

According to the Israeli official, though, a fourth Palestinian prisoner release would go ahead and would include Israeli Arabs, the official added. An additional 400 Palestinian prisoners would be released. Israel would determine those to be released, and they would not have blood on their hands, the official added.

Regarding settlements, there would not be a total freeze, but "Israel will act with great restraint," he said.

But in what one nongovernmental organization's director called "a blow to the American efforts in trying to achieve an agreement between the Israelis and Palestinians," Israel pushed forward Tuesday with tenders for new settlement construction in Gilo, in East Jerusalem.

"Israel today re-announced pushed tenders for 708 new settlement units in Gilo that were originally published in November," said Hagit Ofran, director of Peace Now, an Israeli NGO that monitors Israel's settlement construction in the West Bank and Jerusalem.

The Israeli official said Jerusalem would not be included in the provision calling for no tenders for new housing in the West Bank, although work would proceed on tenders already issued, the official said. The halt on new tenders refers to housing only. Construction of other infrastructure, such as roads and hospitals, he said, would continue.

Asked about the talks and a possible release, Asher Mivzari, a spokesman for The Free Jonathan Pollard Committee, said the committee was not "reacting to the news."

"Their message all along has been that Jonathan Pollard should have been freed a long time ago and this should be an outcome of justice in the American legal system," he said.

Separately, a spokesman for Cabinet Minister Uri Ariel confirmed he had said he was against the release of "murderers" in exchange for Pollard.

Israel has in the past tried to link Pollard's release to peace negotiations. Current and former U.S. officials and experts have suggested the United States government might tie his release to a comprehensive peace deal between the Israelis and Palestinians.

Pollard is up for parole consideration in November 2015, and the United States is running out of time to use his possible release for leverage with Israel.

Carney, the White House spokesman, said on Monday that it is a "complicated issue" and declined to "get into details" about the negotiations.

"And with regards to Mr. Pollard, he is a person who was convicted of espionage and is serving his sentence, and I don't have any update on his situation," Carney said.

But the fact the United States is apparently willing to discuss his release before even a framework agreement has been reached between the parties shows the extraordinary efforts Washington is making to salvage the troubled negotiations.

When asked whether Pollard was a topic in Kerry's talks with Israeli Prime Minister Benjamin Netanyahu, State Department spokeswoman Jen Psaki stuck to the White House line and said she had no updates on his status.

Talks hit asnag

The peace negotiations, which began in July, have hit a snag over whether Israel will agree to release more than two dozen prisoners, including 14 Arab Israelis whom Israel considers terrorists. They were scheduled to be freed on March 29, and now Palestinian negotiators are threatening to end the negotiations over the delay.

Israel has already released three groups of prisoners, most of whom have served lengthy prison terms for attacks on Israelis. But this final release is especially contentious because it includes convicted murderers. Netanyahu has said he would seek approval for any further releases with his Cabinet, which has been critical of the previous releases.

Israeli Deputy Defense Minister Danny Danon told CNN he will resign if Israel goes ahead with the prisoner release, and other Likud Party members in the Cabinet, along with members of the HaBayit HaYahudi Party, which has 12 members in the Knesset, could join him, creating a political crisis.

Netanyahu has also said he would not release any more prisoners if Abbas did not agree to continue negotiations and to stop threatening to seek recognition for Palestinians before international bodies.

A new possible stumbling block in the overall talks arose Tuesday, when Abbas signed 15 requests to have his government join international organizations, according to Palestinian lawmaker Mustafa Barghouti.

Asked about this development, Kerry said none of the organizations that Abbas asked to join "involved the U.N." Furthermore, he scuttled any thought that this could derail negotiations while insisting that the key players remain engaged.

The United States is ready and willing to play a significant role, Kerry said.

Still, Kerry stressed that it's the Israelis and Palestinians who will ultimately decide if a deal gets done.

"In the end, this is up to the parties," he said. "... The leaders have to make the decisions."